Bacterial Contamination Testing and Cleaning Up Sewage Backups in Buildings.

Having your building checked for indoor air quality or other contaminants which may affect occupant health should not omit inspecting and taking site history for evidence of sewage or septic system backups into the structure or basement or crawl space areas below the structure. Black water (sewage) or gray water can cause a wide range of bacteriological, fungal, viral, and parasitic hazards in buildings.

If the occurrence happened only once or if you have had multiple sewage leaks in your building, the concern would arise if prompt and competent cleaning were not performed. If numerous sewage contaminations have occurred, more extensive building cleaning and treatment are likely to be required. This is important to prevent the risk of contamination of bacterial contamination to other areas of the building, especially where human habitation exists.

For example movement of people from contaminated areas to other building areas by tracking contaminated dust and soil, and air movement of aerosolized/contaminated dust particles through a building by natural convection, HVAC equipment or other sources of air and dust movement.

Sewage or Septic Contamination Testing

There are many pathogens in sewage that are harmful to building occupants. Testing for this problem usually focuses on indicator organisms including Escherichia coliform (E. coli), and Enterococcus, total coliform and fecal coliform as these species are expected in human sewage waste. They are potentially harmful themselves as well as serving as an indicator of sewage contamination.

Test sampling in buildings involves using sterile swabs on surfaces in the contaminated areas and in a control area where low or no contamination is expected. Bulk samples of debris or building materials may also be collected, such as drywall suspected of having been wet with a sewage backup. Only a qualified laboratory will be able to properly evaluate submitted samples.

Data source

Data are from the 2009 to 2011 Canadian Health Measures Survey (CHMS). The CHMS collected data from a nationally representative sample of Canadians aged 3 to 79 years from 18 collection sites across Canada. Basic demographic and health information was collected during a household interview, followed by a series of direct physical measurements taken at a mobile examination centre. Blood and urine samples were collected from consenting respondents aged 3 to 79. The CHMS measured lead in blood samples.

BACTERIA & Lead

Here is some information you should know about sewage backups. If you have had a sewage backup or burst house drain pipe in your building, you should be informed of the following:

11%

In 2009 to 2011, 100% of Canadians aged 3 to 79 had lead in their blood; however, almost all of the Canadian population had blood lead levels lower than the current blood lead intervention level of 10 µg/dL. The average lead level for 6 to 79 year olds was 1.2 µg/dL. This is about 11% lower than the average level reported in 2007 to 2009 and four times lower than the average level measured in the 1978 to 1979 Canada Health Survey.

As was the case in 2007 to 2009,Note 4 blood lead levels were higher among:

People with lower household incomes compared to those with the highest household incomes;

People born outside Canada compared to those born in Canada;

People who live in homes that are more than 50 years old compared to those that live in homes that are less than 20 years old; and

People who are current smokers or drink alcohol once or more a week compared to those that never smoke or drink alcohol less than once per week.

Several other factors

Higher in males

Children aged 3 to 5 years had blood lead levels of 0.93 µg/dL which is higher than the levels found in children and youth aged 6 to 19 (Chart 1). Adults aged 60 to 79 had the highest lead levels, reaching 1.9 µg/dL. Males tend to have higher lead levels than females in all age groups, except in children aged 6 to 11 years where there is no difference in lead concentrations. The survey was not designed to provide estimates by sex for children aged 3 to 5.